Abstract: An automated portable call collection unit (APCCU) may gather information used in testing the accuracy of a wireless mobile device locating system. A GPS ground truth detector may detect the location of the APCCU based on GPS signals. A cellular GPS detector may detect GPS signals identified by a signal-identification communication from the locating system. An internal clock may keep time and synchronize its time to GPS time as announced periodically by GPS time signals. A controller may repeatedly cause a cellular network communication system to wirelessly request and receive the signal-identification communication and to send the information about the detected GPS signals, the locations, and the times. All of this may be done in a manner that insures that the accuracy of the locating system is not tested before the internal clock is first synchronized to GPS time following application of operating power to the APCCU.